﻿using System;
using System.Diagnostics;
using System.Globalization;
using System.Runtime.InteropServices;
using System.ComponentModel.Design;
using Microsoft.Win32;
using Microsoft.VisualStudio;
using Microsoft.VisualStudio.Shell.Interop;
using Microsoft.VisualStudio.OLE.Interop;
using Microsoft.VisualStudio.Shell;
using EnvDTE;
using ProcedureList.Library.UI;
using ProcedureList.Library.Presenters;
using System.IO;
using System.Text;

namespace Andre.ProcedureList
{
    /// <summary>
    /// This is the class that implements the package exposed by this assembly.
    ///
    /// The minimum requirement for a class to be considered a valid package for Visual Studio
    /// is to implement the IVsPackage interface and register itself with the shell.
    /// This package uses the helper classes defined inside the Managed Package Framework (MPF)
    /// to do it: it derives from the Package class that provides the implementation of the 
    /// IVsPackage interface and uses the registration attributes defined in the framework to 
    /// register itself and its components with the shell.
    /// </summary>
    // This attribute tells the PkgDef creation utility (CreatePkgDef.exe) that this class is
    // a package.
    [PackageRegistration(UseManagedResourcesOnly = true)]
    // This attribute is used to register the informations needed to show the this package
    // in the Help/About dialog of Visual Studio.
    [InstalledProductRegistration("#110", "#112", "1.0", IconResourceID = 400)]
    // This attribute is needed to let the shell know that this package exposes some menus.
    [ProvideMenuResource("Menus.ctmenu", 1)]
    [Guid(GuidList.guidProcedureListPkgString)]
    public sealed class ProcedureListPackage : Package
    {
        /// <summary>
        /// Default constructor of the package.
        /// Inside this method you can place any initialization code that does not require 
        /// any Visual Studio service because at this point the package object is created but 
        /// not sited yet inside Visual Studio environment. The place to do all the other 
        /// initialization is the Initialize method.
        /// </summary>
        public ProcedureListPackage()
        {
            Trace.WriteLine(string.Format(CultureInfo.CurrentCulture, "Entering constructor for: {0}", this.ToString()));
        }



        /////////////////////////////////////////////////////////////////////////////
        // Overriden Package Implementation
        #region Package Members

        /// <summary>
        /// Initialization of the package; this method is called right after the package is sited, so this is the place
        /// where you can put all the initilaization code that rely on services provided by VisualStudio.
        /// </summary>
        protected override void Initialize()
        {
            Trace.WriteLine (string.Format(CultureInfo.CurrentCulture, "Entering Initialize() of: {0}", this.ToString()));
            base.Initialize();

            // Add our command handlers for menu (commands must exist in the .vsct file)
            OleMenuCommandService mcs = GetService(typeof(IMenuCommandService)) as OleMenuCommandService;
            if ( null != mcs )
            {
                // Create the command for the menu item.
                CommandID menuCommandID = new CommandID(GuidList.guidProcedureListCmdSet, (int)PkgCmdIDList.cmdidMyCommand);
                MenuCommand menuItem = new MenuCommand(MenuItemCallback, menuCommandID );
                mcs.AddCommand( menuItem );
            }
        }
        #endregion

        int OffsetToLineNumber(string text, int offset)
        {
            int lineNumber = 0;
            int pos = 0;
            using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(text)))
            {
                ms.Position = 0;
                using (var sr = new StreamReader(ms))
                {
                    while (!sr.EndOfStream)
                    {
                        var line = sr.ReadLine();
                        pos += line.Length + 2;
                        lineNumber++;
                        if (pos >= offset)
                        {
                            return lineNumber;
                        }
                    }		            
                }            
            }
            return lineNumber;
        }


        /// <summary>
        /// This function is the callback used to execute a command when the a menu item is clicked.
        /// See the Initialize method to see how the menu item is associated to this function using
        /// the OleMenuCommandService service and the MenuCommand class.
        /// </summary>
        private void MenuItemCallback(object sender, EventArgs e)
        {
            var app = (EnvDTE.DTE)GetService(typeof(SDTE));
            if (app.ActiveDocument != null && app.ActiveDocument.Type == "Text")
            {

                var selection = (TextSelection)app.ActiveDocument.Selection;
                var savedOffset = selection.ActivePoint.AbsoluteCharOffset;
                selection.SelectAll();
                string text = selection.Text;
                selection.Cancel();
                selection.MoveToAbsoluteOffset(savedOffset);

                var view = new FormProcedureList();
                var presenter = new ProcedureListPresenter(view, text);
                presenter.Load();
                view.ShowDialog();

                if (view.SelectedMethod != null)
                {
                    //selection.MoveToAbsoluteOffset(view.SelectedMethod.Position);
                    var line = OffsetToLineNumber(text, view.SelectedMethod.Position);
                    selection.GotoLine(line);
                }
               
               /* var f = new FormGotoMethod();
                f.GotoPosition = (pos) => selection.MoveToAbsoluteOffset(pos);
                var methods = GetMethods(text).ToList();
                f.BindMethods(methods);*/

                //f.richTextBox1.Text = text.Selection.Text;
              //  f.Show();
            }
        }

    }
}
